Google calls for improvements in server energy efficiency

Google engineer Luiz André Barroso has claimed a new approach to energy efficiency in servers is urgently needed. In his talk at the O'Reilly Velocity Conference on Monday evening in Burlingame, California, he said that although there have been clear improvements in the energy management of mobile equipment in recent years, transferring these developments to servers is by no means straightforward. Barroso said that maximizing the efficiency and lowering the power consumption of a server required a completely different approach to that used for mobile devices. Google's servers – unlike mobile devices – were rarely idle. Barroso based this claim on his own study of 5,000 Google servers performing four different Google applications.

According to CNET, Google is calling for the development of equipment that reduces power during periods of lower activity rather than just during idle. However, as Barroso pointed out, the fact that servers still consume about half peak power when at zero activity remains problematic. While processors have already gone a long way towards reducing energy consumption at lower loads, hard drives, memory and network adapters are still much worse in this respect. We already have hard disks that can slow down their rotational speed to save power when they are idle, but "they need to bump to higher RPM to read and write, unlike processors, which can actually still process data when in low-activity modes."

It is not clear how many servers Google operates, and the search engine giant isn't telling. According to Pingdom, Google has a total of 36 data centres worldwide: 19 in the USA, 12 in Europe, 3 in Asia and one each in South America and Russia. Estimates put the number of Google servers in the hundreds of thousands.

(trk)